 | ActiveX Controls Guide (v10) |  |
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The CacheRows property determines the maximum number of rows to return in any single Pervasive PSQL extended fetch operation.
The highest possible setting for this property will depend upon the byte length of the returned rows, which in turn is dependent upon the value of the SelectedFields property if there is one, or the defined data buffer length of the data file if there is not. This property corresponds to the "number of records to be retrieved" parameter in the fixed portion of the data extractor in the extended get operation structure (see the Get Next Extended documentation in the Pervasive PSQL Programmer's Guide).
Setting this property to zero will automatically calculate and use the maximum value possible based on the length of the rows to be returned and the value of the MaxBufferSize property. You may set this property to a lower value to optimize read times for a given query.
Setting this value too high will result in a status 97, meaning that Pervasive PSQL has not been configured to handle a buffer large enough to hold the number of rows requested. To solve this problem, lower the setting of the CacheRows property, increase the Pervasive PSQL buffer size (if possible), or reduce the number of fields returned with the SelectedFields property.
The ExtendedOps property must be set to True to enable the extended operations capabilities of the VAccess control.
Affects: Rows
Affected by: ExtendedOps, MaxBufferSize, SelectedFields, Init
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